Go to your Control Panel and click on Uninstall Software. Find and click on WildTangent Games. Only uninstall the Upload App. You will get a checklist of your games and the App should be at the top. Uninstall it, not your games. Come back to the site here and download the App. The WildTangent Desktop icon will uninstall, but downloading the App on the website will reinstall it.
Run WildTangent the same way you usually do from the Desktop icon. Worked very easily for me.